888 Li Ion Batteries on Fire

TheOnlyDocc · 2019-01-10T22:19:23.000Z

There are for sure more and bigger Battery fires to find but it is still a wakeup call everytime i see it.
I talked to a friend today about his way of charging his Li Ion batteries (I would not do it this way and if i had to i would not go outside the room aslong the batteries are charged up).
And when i get home another friend send me this link. Fits together real nice

CRX · 2019-01-10T22:28:51.000Z

Nasty.

ChrisGarrett · 2019-01-10T22:29:06.000Z

Imagine the lung damage?

I wouldn’t be shoveling that shit up if you paid me.

Chris

Enderman · 2019-01-10T23:13:28.000Z

Lithium batteries explode when you light them of fire or physically puncture them.

Batteries alone are actually very safe.
If you overcharge or short them they will usually just heat up at a lot and then cool down.
Worst case scenario they vent.

Lexel · 2019-01-10T23:40:16.000Z

Enderman:

Lithium batteries explode when you light them of fire or physically puncture them.

Batteries alone are actually very safe.
If you overcharge or short them they will usually just heat up at a lot and then cool down.
Worst case scenario they vent.

but in such a contained space with other batteries around it it can make the whole pack go thermal runaway

BlueSwordM · 2019-01-10T23:57:51.000Z

I will copy paste my comment from DIYPowerwalls.com:

Not only is he not using a BMS, he’s charging a lithium ion battery pack with a “48V” lead acid battery charger.

This probably was cause by the golf cart type charger, as it was “48v”

12s * 4.2v/cell = 50.4v max charge voltage.

No problem here, right? No! 48V is the nominal voltage of a 4S 12V lead acid battery system!

The problem is that, Rich, the guy known for being smart and knowledgeable, didn’t think much about battery chemistry, as 12V is their nominal voltage, and they can easily reach a max charging voltage of 14,4V, or even 15V under bad conditions.

So the “48v” charger is actually putting out up to 60V!

57.6v / 12cells = 4.8v per cell (up to 5v if 60v charger). Oops!

So of course the whole pack cooked off. It was massively, massively, massively overcharged.

ChrisGarrett · 2019-01-11T00:21:24.000Z

I don’t know about the rest of you, but that video sure did show ‘venting with flame;’ however, maybe it’s just me?

Chris

EasyB · 2019-01-11T00:22:40.000Z

Another thread on this.

Interesting Tesla battery fire Rechargeable Batteries

[My first Tesla Battery Fire] Interesting YouTube clip.

Boaz · 2019-01-11T00:29:23.000Z

venting isn't worst case scenario ...Bursting into flames is .

There has been a question if vented gas is dangerous or if it is toxic fumes from burning cells.

I'm betting it's not door #1

TheOnlyDocc · 2019-01-11T00:39:16.000Z

And that was very similar to what i have seen at my friends. He was charging the cells with a simple Constant Voltage Power Supply. So when the cells where empty the charge current was way to high.
And measuring (i had my DMM in the car) the voltage showed 4,35V instead of 4,2V (the internal display of the adjustable Powersupply was showing 4,2V). So first he was cooking the cells because of very high charge current and then he overcharged the cells.
The best was, he left the setup in his shop (over night) so that he has fresh charged cells in the morning. I told him that he is lucky to have a shop in the morning. Have i mentioned that the cells are from an “old” Sonly Laptop.
Next time i am driving to him he gets my old I2 Charger (for free). I do not need it anymore.

ChrisGarrett · 2019-01-11T00:45:01.000Z

Boaz:

venting isn’t worst case scenario …Bursting into flames is .

There has been a question if vented gas is dangerous or if it is toxic fumes from burning cells.

I’m betting it’s not door #1

Yeah, ask yourself if you want to breath that stuff?

Trust me, it’s not healthy.

Chris

Lexel · 2019-01-11T01:28:44.000Z

Overcharging with over 4.8V per cell is a guranteed way to start fireworks on a battery pack